PrologClause (prolobjectlink-jpi 1.2-SNAPSHOT API)

All Superinterfaces:

PrologDocumentable, PrologElement

All Known Implementing Classes:

AbstractClause
```
public interface PrologClause
extends PrologElement, PrologDocumentable
```
Prolog clause is composed by two prolog terms that define a prolog clause, the head and the body. This representation consider the prolog clause body like a single term. If the body is a conjunctive set of terms, the body is an structure with functor/arity (,/2) and the first argument is the first element in the conjunction and the rest is a recursive functor/arity (,/2).

The functor and arity for the clause is given from head term functor and arity.

This class define some properties for commons prolog clause implementations. They are boolean flags that indicate if the prolog clause is dynamic multifile and discontiguos.

This class have several methods to access to the clause components and retrieve some clause properties and information about it.

Additionally this class contains a prolog provider reference for build terms in some operations.

Since:

1.0

Author:

Jose Zalacain

Method Summary

All Methods Instance Methods Abstract Methods Deprecated Methods
Modifier and Type	Method and Description
`<T extends PrologClause> T`	`cast()` Casts the current PrologClause to the class or interface represented by this `Class` object.
`PrologTerm`	`getArgument(int index)` Term located at some given index position in the clause head arguments.
`PrologTerm[]`	`getArguments()` Term arguments present in the clause head.
`int`	`getArity()` Integer number that represent the arguments number in the clause head.
`PrologTerm`	`getBody()` Prolog term that represent the clause body.
`PrologTerm[]`	`getBodyArray()` Get the clause body as terms array.
`Iterator<PrologTerm>`	`getBodyIterator()` Iterator to iterate over all body terms.
`String`	`getFunctor()` String that represent the functor in the clause head.
`PrologTerm`	`getHead()` Prolog term that represent the clause head.
`String`	`getIndicator()` Clause family functor/arity based indicator.
`PrologIndicator`	`getPrologIndicator()` Clause family PrologIndicator based indicator.
`PrologTerm`	`getTerm()` Prolog term representation of the current clause.
`boolean`	`hasIndicator(String functor, int arity)` Check if the current clause have functor/arity based indicator specified by arguments, false in otherwise.
`boolean`	`isDirective()` True if this clause is a directive, false in other case.
`boolean`	`isDiscontiguous()` Deprecated. Natives engine don't offer information about that.
`boolean`	`isDynamic()` Deprecated. Natives engine don't offer information about that.
`boolean`	`isFact()` True if this clause is a fact, false in other case.
`boolean`	`isFunction()` True if this clause is a function, false in other case.
`boolean`	`isMethod()` True if this clause is a rule, false in other case.
`boolean`	`isMultifile()` Deprecated. Natives engine don't offer information about that.
`boolean`	`isRule()` True if this clause is a rule, false in other case.
`boolean`	`unify(PrologClause clause)` Check that two clauses unify.

Methods inherited from interface io.github.prolobjectlink.prolog.PrologElement
isClause, isTerm

Methods inherited from interface io.github.prolobjectlink.prolog.PrologDocumentable
getAuthor, getDescription, getSee, getSince, getVersion, hasAuthor, hasDescription, hasDocumentation, hasSee, hasSince, hasVersion, setAuthor, setDescription, setSee, setSince, setVersion

- Method Detail
  - getArity
```
int getArity()
```
    Integer number that represent the arguments number in the clause head. The arity for this clause can be implemented like getHead().getArity().
    
    Returns:
    
    the arguments number in the clause head.
    
    Since:
    
    1.0
  - getFunctor
```
String getFunctor()
```
    String that represent the functor in the clause head. The functor for this clause can be implemented like getHead().getFunctor().
    
    Returns:
    
    the functor in the clause head
    
    Since:
    
    1.0
  - getArguments
```
PrologTerm[] getArguments()
```
    Term arguments present in the clause head.
    
    Returns:
    
    Term arguments present in the clause head.
    
    Since:
    
    1.0
  - getArgument
```
PrologTerm getArgument(int index)
```
    Term located at some given index position in the clause head arguments.
    
    Parameters:
    
    index - position to retrieve the correspondent term.
    
    Returns:
    
    Term located at some given index position.
    
    Throws:
    
    ArrayIndexOutOfBoundsException - if the index value is out of term array bound.
    
    Since:
    
    1.0
  - getTerm
```
PrologTerm getTerm()
```
    Prolog term representation of the current clause. This prolog term is a structure with functor/arity (:-/2) and the arguments head and body.
    
    Returns:
    
    term representation of the current clause.
    
    Since:
    
    1.0
  - getHead
```
PrologTerm getHead()
```
    Prolog term that represent the clause head.
    
    Returns:
    
    the clause head.
    
    Since:
    
    1.0
  - getBody
```
PrologTerm getBody()
```
    Prolog term that represent the clause body. If the clause body representation it's not the term itself, the prolog term should be created and returned.
    
    Returns:
    
    the clause body.
    
    Since:
    
    1.0
  - getIndicator
```
String getIndicator()
```
    Clause family functor/arity based indicator. The clause family indicator is the same indicator for all clauses head in the clause family.
    
    Returns:
    
    functor/arity based indicator of the current clause family.
    
    Since:
    
    1.0
  - hasIndicator
```
boolean hasIndicator(String functor,
                     int arity)
```
    Check if the current clause have functor/arity based indicator specified by arguments, false in otherwise.
    
    Parameters:
    
    functor - clause functor to be checked
    
    arity - clause arity to be checked
    
    Returns:
    
    true if the current clause have functor/arity based indicator specified by arguments, false in otherwise.
    
    Since:
    
    1.0
  - isDirective
```
boolean isDirective()
```
    True if this clause is a directive, false in other case. The implementation for this method can be getHead()==null && getBody()!=null.
    
    Returns:
    
    whether this clause is a directive.
    
    Since:
    
    1.0
  - isFact
```
boolean isFact()
```
    True if this clause is a fact, false in other case. The implementation for this method can be getHead()!=null && getBody()==null.
    
    Returns:
    
    whether this clause is a fact.
    
    Since:
    
    1.0
  - isRule
```
boolean isRule()
```
    True if this clause is a rule, false in other case. The implementation for this method can be getHead()!=null && getBody()!=null.
    
    Returns:
    
    whether this clause is a rule.
    
    Since:
    
    1.0
  - isMethod
```
boolean isMethod()
```
    True if this clause is a rule, false in other case. The implementation for this method can be getHead()!=null && getBody()!=null.
    
    Returns:
    
    whether this clause is a rule.
    
    Since:
    
    1.1
  - isFunction
```
boolean isFunction()
```
    True if this clause is a function, false in other case. The implementation for this method can be getHead()!=null && getBody()!=null.
    
    Returns:
    
    whether this clause is a rule.
    
    Since:
    
    1.1
  - unify
```
boolean unify(PrologClause clause)
```
    Check that two clauses unify. Prolog clauses unify if and only if the head and the body for both clauses unify.
    
    Parameters:
    
    clause - the clause to unify with the current clause
    
    Returns:
    
    true if the given clause unify whit the current clause, false otherwise
    
    Since:
    
    1.0
  - isDynamic
```
@Deprecated
boolean isDynamic()
```
    Deprecated. Natives engine don't offer information about that.
    
    True if this clause is a dynamic, false in other case
    
    Returns:
    
    whether this clause is a dynamic
    
    Since:
    
    1.0
  - isMultifile
```
@Deprecated
boolean isMultifile()
```
    Deprecated. Natives engine don't offer information about that.
    
    True if this clause is a multifile, false in other case
    
    Returns:
    
    whether this clause is a multifile
    
    Since:
    
    1.0
  - isDiscontiguous
```
@Deprecated
boolean isDiscontiguous()
```
    Deprecated. Natives engine don't offer information about that.
    
    True if this clause is a discontiguos, false in other case
    
    Returns:
    
    whether this clause is a discontiguos.
    
    Since:
    
    1.0
  - getPrologIndicator
```
PrologIndicator getPrologIndicator()
```
    Clause family PrologIndicator based indicator. The clause family indicator is the same indicator for all clauses head in the clause family.
    
    Returns:
    
    PrologIndicator based indicator of the current clause family.
    
    Since:
    
    1.0
  - getBodyIterator
```
Iterator<PrologTerm> getBodyIterator()
```
    Iterator to iterate over all body terms.
    
    Returns:
    
    Iterator to iterate over all body terms.
    
    Since:
    
    1.0
  - getBodyArray
```
PrologTerm[] getBodyArray()
```
    Get the clause body as terms array.
    
    Returns:
    
    clause terms body array.
    
    Since:
    
    1.0
  - cast
```
<T extends PrologClause> T cast()
```
    Casts the current PrologClause to the class or interface represented by this Class object.
    
    Returns:
    
    the PrologTerm after casting, or null if term is null
    
    Throws:
    
    ClassCastException - if the object is not null and is not assignable to the type T.
    
    Since:
    
    1.1

Interface PrologClause

Method Summary

Methods inherited from interface io.github.prolobjectlink.prolog.PrologElement

Methods inherited from interface io.github.prolobjectlink.prolog.PrologDocumentable

Method Detail

getArity

getFunctor

getArguments

getArgument

getTerm

getHead

getBody

getIndicator

hasIndicator

isDirective

isFact

isRule

isMethod

isFunction

unify

isDynamic

isMultifile

isDiscontiguous

getPrologIndicator

getBodyIterator

getBodyArray

cast